1. Technical Field
The present disclosure relates to light guides and backlight modules using the same, and particularly, to a light guide ring unit and backlight module using the same.
2. Description of the Related Art
Backlight modules often provide illumination for electronic devices such as an instrument panel, a keyboard or other.
A commonly used backlight module includes a light guide ring unit and a plurality of light emitting diodes. The light guide ring unit includes an annular light incidence surface and an annular light-emitting surface opposite to the light incidence surface. The light emitting diodes are arranged on the annular light incidence surface. The annular light incidence surface receives light emitted from the annular light emitting diodes, the light is propagated in the light guide ring plate, and exits via the annular light-emitting surface. However, the brightness of the annular light-emitting surface located at a distance away from the light emitting diodes is lower than that of the light incidence surface, which is adjacent to the light emitting diodes, such that the brightness of the light guide ring unit is not uniform. In addition, the cost of the backlight module is unduly high due to the requirement for having multiple light emitting diodes.
Therefore, there is room for improvement within the art.